August 9, 2012
A Penton Media Publication
Tune in to EngineeringTV.com
200 mph
and
BATTERY
POWERED
page 20
FOCUS on
ENERGY
WILL NATURAL GAS
POWER OUR CARS
AND TRUCKS?,
page 40
HOW TO MAKE
PNEUMATICS
MORE ENERGY
EFFICIENT,
page 44
ULTRACAPACITORS
HOP UP
MICROHYBRIDS,
page 48
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© COPYRIGHT 2012 OMEGA ENGINEERING, INC. ALL RIGHTS RESERVED
VOLUME 84
ISSUE 11
AUGUST 9, 2012
ENERGY EFFICIENCY
Chrysler had already
adapted several of its
vehicles, including the
Ram truck, to bifuel
technology, letting
them run on natural
gas or gasoline. Such
vehicles could help
make the transition to
vehicles predominantly
powered by natural gas.
FEATURES
Should the U. S. switch to
natural
gas
for
transportation?
motorcycle
20 Electric
tops 200 mph
Rocket, an electric dragster, set
the quarter-mile record not only
for electric motorcycles, but for all
electric vehicles.
The technology
and gas is readily
available. And it could
save the U. S. over
$200 billion annually.
40
MACHINE DESIGN.com
Americans spend about $260 billion each year on oil from outside of NAFTA
for transportation. This transfer of capital to other countries increases our
national debt and interest load. Fortunately, analysis shows that we can
quickly convert vehicles to domestic natural gas, which would let Americans
remain mobile, keep the environment clean, and provide trillions of dollars
over the next half century for developing alternative energy and transportation options for the long-term future.
What the U. S. needs
In terms of energy, the U. S. gets about 14.78 quads (1015 Btu) for its $260 billion. A trillion ft3 (Tcf) of natural gas contains approximately one quad. So 14.78
quads used for transportation per year can be replaced with 14.78 Tcf of natural
AUGUST 9, 2012
Honda leases its hydrogenpowered FCX Clarity in
California. Here is one at a
hydrogen refueling station
that gets it hydrogen direct
from a pipeline.
Standards are already in place to govern the safe operation of natural-gas
fuel stations, like this one.
Authored by:
Dick Medvick
Contributing Editor
Cleveland, Ohio
Edited by Stephen J. Mraz
[email protected]
For more on natural-gas vehicles, scan this
code or go to: http://
machinedesign.com/
article/uneven-prospectsfor-natural-gasvehicles-0810
gas. That might seem like a lot of natural gas, but last year
the U. S. Potential Gas Committee reported that the U. S.
has at least 2,170 Tcf.
America currently uses 23.37 quads from natural gas
each year for residential, commercial, transportation, and
industrial applications — either directly, or by generating
electricity. Adding another 14.78 quads for transportation would push the total use to 38.15 quads per year, or
38.15 Tcf of natural gas. At this rate, 2,170 Tcf of natural
gas would last a minimum of 57 years. In addition, Canada
has at least another 780 Tcf of natural gas, the equivalent
of another 20 years of gas use. So there’s plenty of natural
gas, and converting transportation to it could save North
American consumers $20 trillion ($260 billion annually
for 77 years). That’s money that could fund research and
development into new sources of safe and clean energy
and transportation.
Current NGV
CSA America, the organization that writes standards
for gas appliances and accessories and alternative-energy
products, has already written standards for compressed
natural-gas vehicles (NGV) and filling stations. The design work is done, and NGVs are in dealers’ showrooms.
Honda, for example, sells NGVs which store natural gas at
3,600 psig. Other automobile manufacturers could quickly
follow suit.
And natural gas in its liquid form (LNG) is already
becoming popular for long-haul trucking. It costs about
$1.50 less for the equivalent of a gallon of diesel fuel, which
can lead to significant savings for truckers routinely buying 20,000 gallons of diesel fuel annually.
In fact, several truck and engine manufacturers offer
LNG models, including Cummins-Westport, Kenworth,
PACCAR-owned Peterbilt, Navistar, Freightliner, and
Caterpillar. LNG trucks still cost more, but as more models are available, costs are coming down to the point many
models pay back the price premium with the first year of
savings on fuel.
But there are problems with NGVs: Customers won’t
buy them because there aren’t enough natural-gas filling
stations and companies won’t install filling stations because there are not enough NGVs on the road.
For truckers, this chicken-and-egg dilemma is being
partly solved by an agreement between Clean Energy
Fuels, a national natural gas supplier, and Pilot/Flying J
truck stops. They plan to install refueling pumps at 150
locations along major interstate trucking routes by the
end of next year, then add at least 100 more. The goal is to
make it possible for an LNG truck to travel coast to coast
and border to border — anywhere a diesel rig can go.
For consumer cars and trucks, the solution to the fillingstation problem might be in the hands of the auto companies. They could design and sell bifuel vehicles, which run
AUGUST 9, 2012
40
the U. S. switch
40 Should
to natural gas for
transportation?
Switching to natural gas could end
U. S. dependence on foreign oil for its
transportation needs.
ENERGY EFFICIENCY
Getting
ENERGY
SAVINGS
44
from pneumatic systems
Getting energy savings
from pneumatic systems
There are three basic ways
to boost the efficiency of
industrial pneumatics.
There are three basic ways to
boost the efficiency of industrial
pneumatics.
Industrial machines and production systems that are
designed to run efficiently and save energy are undoubtedly important considerations in manufacturing today.
The reasons not only include rising energy prices and
the need to hold down production costs, but also an
increasing awareness of the environmental impact on an
organization’s sustainability.
All of these issues should not simply be the responsibility of production-floor personnel. Machine and system
designers and financial managers of industrial and manufacturing corporations have a stake in this as well.
With pneumatic systems, there are basically three different ways to approach energy savings: leak detection,
design, and advanced machine diagnostics. Here’s a closer
look at each.
Leak detection
a cap in it!
48 Put
The rapid charge and discharge
ability of ultracapacitors opens a
myriad of uses for quick and cleanenergy-storage needs.
A good leakage-management program is essential. It
radically lowers compressed-air consumption and the associated costs as leaks are a waste of compressed air, which
translates into lost energy and money. In addition, leaks
create pressure losses that can significantly slow production processes and prevent machines from running at
peak capacity.
A study by the Fraunhofer Institute in Germany
looked at compressed-air systems in the European Union
and concluded that 42% of the total potential savings
in optimizing pneumatic systems comes from simply
implementing a solid leak-detection program. The
objective should be to completely check the pneumatic
system from the compressor (supply side) to each machine
and device (demand side). On the demand side, using a
simple ultrasonic leak detector can help manually identify individual leaks on machines — usually for an entire
The energy-efficient
OVEM vacuum
generator has an
integrated filter and
sensors that monitor
the status of the
vacuum system.
44
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AUGUST 9, 2012
44
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ON THE COVER
Larry “Spiderman” McBride
gets ready to drive the Rocket
to its 200+ mph run.
DEPARTMENTS
8 EDITORIAL
Risk, benefits, and mental mistakes
10 EDITORIAL STAFF
12 LETTERS
16 SCANNING FOR IDEAS
Rotary actuator increases speed, rotation, and response while
cutting costs
Gear drives reliably transmit power
20
28
35
36
REPORTER’S NOTEBOOK
LOOKING BACK
SENSOR SENSE
COMMENTARY
Two sides of a green-energy failure
38 VANTAGE POINT
Educating the next generation of engineers — Sasha Gurke
39 INVENTOR’S CORNER
52 FE UPDATE
Analysis helps subsea cables survive
55 SOFTWARE PRODUCTS
56 PRODUCT SPOTLIGHT
Bearings & guides
57
60
61
62
62
63
PRODUCTS
AD INDEX
BUSINESS INDEX
CLASSIFIEDS
BUSINESS STAFF
BACKTALK
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AUGUST 9, 2012
POSTMASTER: Send change of address notice to
Customer Service, MACHINE DESIGN, P.O. Box 2100, Skokie,
IL 60076-7800.
Intelligent fans for
smart savings.
Most axial fans of the “compact class” use the old shaded-pole motor AC technology, despite its
poor efficiency compared to DC technology. The barrier to improvement was that DC technology
couldn’t be operated directly from the AC mains supply. A solution is now available with i-Maxx
technology from ebm-papst. The i-Maxx retains the mounting dimensions of the equivalent AC
fans and is capable of operating on AC mains power around the world. There is no simpler way
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the engineer’s choice
RS# 104
What’s new online machinedesign.com
FREE WEBCAST: APPLYING STEPPER MOTORS
Thursday, August 9, 11:00 ET
This Webinar, presented by ElectroCraft, will review basic parameters
necessary to properly select and apply stepper motors to motion applications.
The discussion will review stepper speed-torque behavior, thermal ratings,
engineering calculations, and how windings impact dynamic behavior. Other
topics will include considerations for intermittent-duty operation, motor/system
accuracy, failure modes, and how to apply these criteria to stepper-based linear
actuators. Learn more and register at http://tinyurl.com/d9bfkk9.
Hydraulic-powered go-cart
Hennepin Technical College is teaching students about fluidpower technology and making it fun, too. An instructor shows
off a go-cart powered by fist-sized, 5-hp hydraulic motors that
eliminate gears, clutches, chains, and belts. He also discusses
a mobile picnic table with a hydrostatic drive, a hydraulic
motorcycle, and a pneumatic
lawnmower. View the episode at
www.engineeringtv.com/video/
Hydraulic-Fun-and-TeachingFlui;Fluid-Power-Conference-Expo-201.
EDITOR’S WEB PICKS
Power-transmission site
6
U. S. Tsubaki has launched a new
Web site (http://ustsubaki.com) on its
roller chains, motion-control components, sprockets, and other products for the energy, mining, foodprocessing, forestry, packaging, and
conveyor markets. Content includes
detailed specs and images, videos,
and a library of 2D and 3D CAD
drawings. Users can compare similar
products by characteristics such as
dimensions, materials, and specific
features. And an online configurator
lets users create complex drawings
on demand.
Wireless Web site
The new Linx Technologies Web
site (www.linxtechnologies.com)
covers wireless products such as RF
modules, remote controls, antennas,
connectors, and development kits.
Content includes specs, documentation, application notes, and FAQs
on FCC certification. Users can also
download software and drivers and
get tech support.
Site transforms
hobbies into cash
Jameco Electronics has introduced
its new Club Jameco Web site (www.
ClubJameco.com), where electronics
do-it-yourselfers can design kits for
hobbyists and earn royalties. The site
lets designers create an electronics
project by identifying components,
MACHINE DESIGN.com
writing step-by-step instructions, and
selling the creation as an electronics kit. A “crowd-source” feature lets
members comment and contribute
to the project while it is being designed. Projects will be sourced, built,
promoted, and sold without any cost
or risk to the designer. Club Jameco
also lets electronics enthusiasts discover, discuss, develop, and purchase
electronics kits.
Enclosures catalog
The new North American Edition of
Rittal Corp.’s product catalog is available in electronic or print versions.
Nearly 900-pages long, it covers the
company’s IT and industrial products from large security enclosures
and mobile data centers to junction
boxes, stainless-steel enclosures,
and the nuts and bolts required to
assemble accessories. Get a copy at
www.rittal-corp.com/literature.
Sensors site
Balluff has launched a new Web
site on the company’s inductive,
photoelectric, vision, capacitive and
magnetic sensors, as well as linearposition transducers, RFID systems,
and networking products. The site
includes product data sheets, support material, and literature. Product
selectors let users apply physical, environmental, electrical, and specialduty attributes to identify the mostsuitable product for a design. Learn
more at www.balluff-usa.com.
AUGUST 9, 2012
FREE WEBINARS ON
SENSORS, PROCESS
CONTROL AND MORE
Take 30 to 45 min and watch
free Webinars on industrial
controls topics. Whether live or
prerecorded, see equipment in
action and gain some insight.
SENSORS
This short, 30-min session will
review all types of sensors,
including: photo, proximity,
fiber optic, magnetic, capacitive,
ultrasonic, light curtains, and
more. We will cover real-world
applications and take live
questions.
August 15, 2012, 2:00 p. m. ET
PROCESS CONTROL
This prerecorded 40-min
presentation discusses process
control, and the products that
are useful in those applications.
Learn about devices that
can sense temperature and
pressure; control devices such
as temperature controllers and
PLCs that accomplish PID control;
signal conditioning; and timer
relays that are useful in this area of
automation control.
PNEUMATICS
This prerecorded 40-min session
covers the NITRA pneumatic
product family. The line now
includes stainless-steel cylinders,
filters, regulators, lubricators,
solenoid valves, position switches,
tubing, and fittings. See working
demos and customer examples.
Visit www.automationtalk.com to
check the schedule and register
for upcoming presentations, or
view the prerecorded Webinars on
demand.
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EDITORIAL
Risks, benefits, and
mental mistakes
You are reading our annual energy issue which looks at promising advances
that could change the way we live. It is fair to say that certain energy technologies, particularly in the renewable area, have large, vocal followings. So
we were intrigued by recent work from psychologists who found that many
people make decisions about technology using emotions and mental shortcuts. Interestingly, people doing this generally don’t recognize their thought
process isn’t strictly rational.
The research results ring true partly because researchers stayed away from
politically charged technologies such as energy. Headed up by University of
Oregon psychology Professor Paul Slovic and East-West Center Senior Fellow
Melissa Finucane, the research group surveyed people’s opinions about various topics such as water fluoridation, cars, and food preservatives. They asked
subjects in the study to list both the benefits and risks of each technology.
All in all, the researchers found people based their judgment about a
technology on their feelings for it. People rated those they liked as having
large benefits with little risk. When commenting on technologies they didn’t
like, they could only think of disadvantages; few strong points came to their
minds.
It wasn’t just the uninformed public who were prone to such black-andwhite assessments. Professionals making judgments in their field fell victim
to them as well. In one case, members of the British Toxicology Society found
few benefits in substances they thought were risky, few problems with those
they liked.
There was a second part to Slovic and Finucane’s study. Their group had
respondents read brief arguments in favor of various technologies they’d just
opined on. Some of the arguments focused on the benefits of a technology,
others stressed low risks.
These short passages turned out to be effective at changing the emotional
appeal of the technologies. People who read about the benefits of a technology also changed their mind about its risks; they perceived it as being less
risky. A point to note is that the passage they’d read mentioned nothing at all
about risks. In a similar vein, people only told that the risks of a technology
were mild started to look at its benefits in a more favorable light.
The way we feel about something also tends to make us ignore statistics
even when we understand their implication. Researchers say our responses
to uncertain situations appear to have an all-or-none quality that is sensitive
to the possibility rather than the probability of strong positive or negative
consequences. So events with very small probabilities carry great weight with
most people.
This, they argue, helps explains the impact of big headlines about hazards
such as nuclear power and exposure to extremely small amounts of toxic
chemicals, despite widely available information about the small probabilities
of their feared consequences.
It is not difficult to see how these conclusions pertain to the shrill public
debates surrounding energy policy. People who have pet energy technologies don’t have to face painful trade-offs that are built into embracing them.
Technologies we favor are likely to have few costs. Less favored technologies
are all bad.
In this ideal world, decisions are easy.
— Leland Teschler, Editor
8
RS# 107
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AUGUST 9, 2012
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RS# 108
EDITORIAL STAFF
EDITOR
Leland E. Teschler
[email protected]
MANAGING EDITOR
Kenneth J. Korane
[email protected]
SENIOR EDITORS
Leslie Gordon
[email protected]
Stephen J. Mraz
[email protected]
ASSOCIATE EDITORS
Lindsey Frick
[email protected]
Robert J. Repas, Jr.
[email protected]
RS# 109
INDUSTRY COVERAGE:
AUTOMOTIVE, PACKAGING,
MEDICAL
Stephen J. Mraz
CAD/CAM, MANUFACTURING
Leslie Gordon
ELECTRICAL, ELECTRONICS
Robert J. Repas, Jr.
FASTENING & JOINING,
MATERIALS
Lindsey Frick
FLUID POWER
Kenneth J. Korane
MECHANICAL
Lindsey Frick
Kenneth J. Korane
EDITORIAL PRODUCTION
Denise Greco
Editorial Production Manager
Randall L. Rubenking
Art Director
1300 E. 9th St. Cleveland, OH 44114-1503
10
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RS# 110
AUGUST 9, 2012
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LETTERS
The bright side of
pessimism
“Kennedy asked his fellow Americans to join him in a quest to
end poverty, disease, tyranny,
and war.” (“A Generation of Pessimists,” June 6).
Asking someone to join in a
quest does not mean the goal
is attainable. Nor does it mean
that because the goal is unattainable, one should not try to
achieve it. It is not pessimistic to
believe that these goals are unattainable, merely realistic. Given
that human nature is involved,
it is likely impossible to end all
these things.
Mike Stoneberg
Maybe the reason the younger
generation of students is pessimistic about the future is that
they have a real understanding
of the reasons behind global
warming and are all too often
faced with people who call them
“environmental extremists.”
Engineers should be working
towards solving the real problem
of global warming. They should
be pushing for energy conservation and designing vehicles that
reduce CO2 emissions.
Too often the youth of our nation are faced with people such
as yourself who are standing in
their way.
That’s a real cause of pessimism.
Ed Malec
Perhaps today ’s students are
more obser vant than Horgan
gives them credit for. Perhaps
they are aware of the “success” of
the various War on Poverty programs over the past half century,
which demonstrate the inability
of the government to solve or
cure poverty.
William Kelly
The job prospects for many college
students are terrible, while their
debt levels are astronomical.
These students could probably
live with any of the world’s other
12
MACHINE DESIGN.com
Reasons to be down
R e a d e r s s e e m to s h a re
the opinion that there are
perfectly good reasons to
be pessimistic, especially
when it comes to the government’s ability to help
anyone. They also seem pessimistic about geometrical
dimensioning and tolerancing, an art or science few engineers have mastered.
problems if they knew there was
a decent job waiting for them.
For example, my parents saw the
horrors of World War II, but there
was tremendous economic opportunity in the 50s and 60s and
they quickly became optimistic,
at least about their own futures.
I feel that prosperity has been
redistributed too much toward
the top 1%. That redistribution
was masked for a while by climbing debt, but now that bubble
has burst. That’s the problem.
Steve Oberheim
Lack of experience in
engineering college
With over 27 years of designengineering experience, I’m still
amazed at the lack of practical
design knowledge being taught
— even in the mechanical-engineering departments of major
universities (“Working with Dimensional Tolerances,” May 10). It
appears that most professors understand the math and science
involved in engineering, as that
is what they can test, but they are
clueless when it comes to practical design methods.
During the last several years,
I’ve observed how several
younger mechanical engineers
have approached the machinists
in our model shop. Some told
the machinists: “Just do it the
AUGUST 9, 2012
way I’ve designed it.” The result:
parts that don’t fit, lots of rework,
too much scrap, and a myriad of
other issues that could have been
avoided had the engineer only
spent a little time learning how
to interact with the shop personnel. These guys can — and will
— be the friend of any engineer
who treats them with respect. Insulting the shop personnel just
cuts off the communication you
need to understand how to redimension the part, or tweak the
design for manufacturability —
crucial items, if you want to move
your career forward.
Tim K. Ries
This article makes it sound as if
dimensional tolerances are optional. Not so. Every dimension on
a drawing must have an associated
tolerance, whether specific to that
dimension, or covered by general
tolerances in the title block. Lack
of a tolerance precludes your ability to reject parts made to dimensions you can’t use.
This is usually covered in Engineering Drawing 101. The fact
t h a t m a ny e n gi n e e r s d o n o t
understand this is indicative of
many of the problems we face
today in manufacturing.
Vern Lowry
I have been doing tolerance stack
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Other product and company names listed are trademarks or trade names of their respective companies. 05312
LETTERS
years. The problem in the industry is that everyone believes you
can hire someone to snap a CAD
dimension and throw it over the
wall to manufacturing.
Steve Washeim
What goes around
Your recent cover and associated
article struck a responsive chord
with me (“Better Alternatives for
Wind Power,” May 10). I worked
for one of the National Labs
during President Carter’s uncoordinated lunge in the general
direction of what we now know
as green energy. Someone at another lab conceived the idea of
harvesting the jet stream by flying kites that were conceptually,
if not geometrically, similar to
the one on your cover. That was
in 1980. You might be amused
to know that I drew a cartoon
expressing my general skepticism about the concept. I titled
it the Horizontally Oriented Wind
Generator, Jet stream Oriented,
With Lifting Surfaces. It was to
be known by its acronym: HOWG
JOWLS.
Bob Woods
Software upgrades that
make things worse
Poor design is also rampant in
software (“Form Should Follow
Function, and More,” April 26).
The software companies think
they know what you want, but
then with each update (hardly
an upgrade), they bury the tools
you use 99% of the time under
layers of “sales features.”
This is how Google ruined
their e-mail. I have to make extra
clicks to sign out or find contacts.
And why are there now six types
of contacts to search? I just want
one contact list.
Microsoft also ruined Excel this way. Users now have to
find the basic tools by digging
through layers of new, mostly
unused crap.
Even Britannica succumbed.
They pushed out fundamental
reference data, their supposed
bread and butter, to make room
for the “news.” The CRC handbook
took this same misguided route.
They are all becoming tweets
rather than tools.
All these companies left out the
first step in systems engineering
when “improving” their software:
Assemble the stakeholders, especially the users, and find out how
they really use the tools.
William Elrod
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MACHINE DESIGN.com
AUGUST 9, 2012
RS# 113
Integrated Motion Solutions
(Purchase Order to Shipment)
Groschopp uses the Fast Track™ department to quickly build motors/gearmotors to meet customer’s demands. Because
Groschopp stocks components rather than finished motors/gearmotors, we can easily make modifications to the motor/
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Because our Fast Track™ designs are based on standard product lines our experienced, on site machinists can quickly
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REGISTERED
RS# 114
SCANNING FOR IDEAS
Edited by Stephen J. Mraz
Rotary actuator
increases speed, rotation, and
response while cutting costs
To improve the speed and control of rotary actuators used in laser scanning and other optical systems, engineers at Pangolin Laser Systems,
Orlando, Fla. (www.pangolin.com), decided to take matters into their own
hands and designed a new rotary actuator. The result, the VRAD-1510 is
reportedly capable of higher speeds,
greater range of rotation, faster
responses, and more-precise
shaft movement than other
Precision
actuators. The low-power
bearing
Coil
unit, which is based on an
innovative dual-coil, segmented stator design, also
Magnet
costs about one-third less
than existing rotary actuators. This means the device
could be used in a
End
range of elecStator
block
tromechanical
applications,
including mechanical and
automotive
systems, robotics, HVAC, and
Output
valve control.
Precision
shaft
bearing
Pangolin designers developed a
new and inexpensive way
to make segmented stators
without air gaps, which interfere
with the motor’s magnetic field. The design also uses two, separately accessible
coils, resulting in a compact, quiet, and
durable actuator.
For durability, the actuator uses a magnetic spring and preloaded ball bearings.
the device flexible in terms of how it can be
The unit also does not need mechanical
used. For example, instead of using both
stops on shaft rotation, which eliminates
coils to generate torque, one can be used
much of the noise, wear, and vibration.
for dynamic braking or to sense velocity.
The shaft rotates more than ±60° from
Units can be configured to meet custhe neutral position. The actuator also has
tomers specs in terms of torque factor,
front and rear shafts, letting users add an
magnetic-spring stiffness, coil resistance
encoder or position sensor for closed-loop
and inductance, shaft diameter and length,
bearing preload, and operating temperaoperations, or other optional attachments.
ture range. The rectangular shaped unit
The VRAD-1510 features a linear remeasures 1.5 × 1.0 × 1.5 in.
sponse. So applying twice the voltage gives
RS# 401
twice the output angle; applying three
times the voltage results in three times the
r
formation via ou
output angle.
Request free in Web site at
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The actuator’s coils can be driven in sec
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16
MACHINE DESIGN.com
AUGUST 9, 2012
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RS# 115
SCANNING FOR IDEAS
Gear drives
reliably transmit power
Gear-drive units from Mitrpak, Uxbridge, Mass.
(www.mitrpak.com), have proven reliable for
power transmission for over 30 years in the mostdemanding applications. All of the
drives, including right-angle, threeHardened high-alloy-steel spiral-bevel
way, and counterrotating units,
gears for high speed and loads, and
give users mounting
smooth, quiet operation
flexibility, with each
drive having several
mounting flanges
and body-mounting
surfaces. Customers
can also order special
materials, shaft
extensions, and other
modifications.
The durable drives
use double-shielded,
permanently greased
standard metric ball
bearings, as well
as hardened-alloysteel spiral-bevel
Metric,
gears and aluminum
doublehousings. Stainless-steel
shielded,
shafts are standard. The
permanently
Aluminum
drives’ gear-meshing assembly
lubricated
housing for
gives users quiet, vibration-free
ball bearings
strength and
performance. And a bearing
heat dissipation
locknut makes maintenance
in the field efficient and
economical.
Drives are shipped
Bonded-lip grease seal,
completely enclosed, sealed,
recommended for use in
and lubricated for life with
food and drug industries
Exxon Nebula EP-O. This grease
withstands operating temperatures
from –65 to 250°F. And bonded-lip
grease seals provide positive grease retention,
a feature recommended for food and drugCorrosion-resistant,
handling equipment. Users can also specify
stainless-steel shafts
hardcoated housings and bearing locknuts for
food-processing equipment. Hardcoating is an
electrochemical penetrating process that prevents
peeling and flaking.
Bearing locknut lets users
adjust for maintenance and
Right-angle and three-way units range in weight
meshing gears.
from 2 to 20 lb, can handle inputs from 20 to
4,000 rpm, and transmit 26.3 to 630 lb-in. of torque.
Counterrotating units weigh from 2 to 8 lb, handle
inputs from 100 to 4,000 rpm, and transmit 22 to
189 lb-in. of torque.
RS# 402
18
MACHINE DESIGN.com
AUGUST 9, 2012
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